Laboratory and Field Studies Related to Radionuclide Migration at the Nevada Test Site in Support of the Underground Test Area Program and Hydrologic Resources Management Project October 1, 1999-September 30, 2000

Finnegan, David L. ; Thompson, Joseph L.

Los Alamos National Laboratory

关键词: Management;    Lanl;    Temperature Gradients;    Nevada Test Site;    Radioisotopes;   

DOI  :  10.2172/775922
RP-ID  :  LA-13787-PR
RP-ID  :  W-7405-ENG-36
RP-ID  :  775922

美国|英语

来源: UNT Digital Library

【 摘 要 】

This report details the work of Chemistry Division personnel from Los Alamos National Laboratory in FY 2000 for the US Department of Energy/Nevada Operations Office under their Defense Programs and Environmental Restoration Divisions. Los Alamos is one of a number of agencies collaborating in an effort to describe the present and future movement of radionuclides in the underground environment of the Nevada Test Site. This fiscal year we collected and analyzed water samples from a number of expended test locations at the Nevada Test Site. We give the results of these analyses and summarize the information gained over the quarter century that we have been studying several of these sites. We find that by far most of the radioactive residues from a nuclear test are contained in the melt glass in the cavity. Those radionuclides that are mobile in water can be transported if the groundwater is moving due to hydraulic or thermal gradients. The extent to which they move is a function of their chemical speciation, with neutral or anionic materials traveling freely relative to cationic materials that tend to sorb on rock surfaces. However, radionuclides sorbed on colloids may be transported if the colloids are moving. Local conditions strongly influence the distribution and movement of radionuclides, and we continue to study sites such as Almendro, which is thermally quite hot, and Bilby where radionuclides do not appear to have moved a short distance from the cavity. We have begun field use of a tool that allows us to measure important groundwater properties in situ. We conclude our report by noting document reviews and publications produced in support of this program.